Eclipse Amlen

Overview

Eclipse Amlen is a self-hosted messaging server for connected devices and web applications. It is best suited to teams that need MQTT to work alongside JMS or custom protocols, with controls over how clients use messaging. Its combination of protocol conversion and extensibility gives it range, while its single LDAP connection can constrain identity management.

Key features

Amlen supports MQTT versions 3 through 5 over TCP/IP and WebSockets, as well as JMS, and can convert messages between MQTT and JMS. That makes it useful when device clients and JMS applications need to exchange messages through one server. MQTT clients are supported for C, Java, Android, iOS, and JavaScript, covering common application and device environments.

The protocol plug-in SDK lets teams add custom protocols, including for legacy sensors that cannot use MQTT. This is a meaningful advantage for systems that must accommodate older equipment, but teams with MQTT-only deployments may have little need for that flexibility.

The Amlen Bridge forwards MQTT messages to another MQTT server or IBM Event Streams for IBM Cloud. Filtering, topic mapping, multiple forwarders, and REST APIs for configuration and monitoring give operators practical control over routing. Administrators can also manage message hubs and endpoints through the WebUI or REST Administration APIs.

Security includes TLS profiles, user ID and password authentication against a configured LDAP server, and policies governing connections, topics, subscriptions, and queues. These controls let administrators define which clients can connect and which messaging actions they can take. Amlen supports one LDAP server connection, so organizations that need users and groups from multiple LDAP servers will need another approach.

Pricing

Eclipse Amlen: free. The free plan provides a self-hosted server, with no free trial or separate paid plan described. That makes it accessible for teams able to operate their own deployment; the trade-off is that Amlen's identity setup is limited to one LDAP server connection.

Platforms

Amlen is listed for Android, iOS, Linux, web, API, and self-hosted use. The stable release page offers server and WebUI downloads for RHEL and AlmaLinux 8, 9, and 10, so teams targeting those distributions have a clear deployment path. MQTT clients are also supported for C, Java, Android, iOS, and JavaScript.

Who it's for

Amlen fits IoT and web messaging teams that need MQTT and JMS interoperability, custom protocol extensions, or controlled forwarding between brokers. The product is described as mature and used by large enterprises in production, which may make it relevant to organizations evaluating a self-managed messaging server. Teams needing multiple LDAP connections should look elsewhere.

Pros and cons

• MQTT and JMS conversion: connects device messaging with JMS applications through a single server.
• Protocol plug-in SDK: can accommodate legacy sensors that cannot use MQTT.
• Configurable bridge routing: filtering, topic mapping, and multiple forwarders help direct MQTT traffic across systems.
• Detailed access policies: separate controls cover connections, topics, subscriptions, and queues.
• One LDAP connection: limits identity management to a single LDAP server.

Alternatives

For a wider set of broker options, browse Message Broker Software. Choose Lightstreamer if its freemium model and free demo license for up to 20 concurrent client connections suit your needs. EMQX is another freemium option, with a serverless plan that includes up to 1,000 connections and a usage-based charge beyond its monthly free quota.

Faye is a free alternative under the Apache 2.0 license. Consider HiveMQ MQTT Broker if its Lab plan's 100-connection and 100-messages-per-second limits fit your workload. RabbitMQ offers a free, self-managed open-source server with best-effort community support.

SocketCluster is a free, self-hosted option with no paid plans listed. TIBCO FTL has a free Community Edition download for Windows, Linux, and macOS. Apache Artemis is another free self-hosted broker, licensed under Apache License 2.0 and requiring Java 17 or later.

Verdict

Choose Eclipse Amlen if your self-hosted IoT or web messaging system needs MQTT and JMS conversion, custom protocol support, and policy-based access controls in one server. Its free plan and flexible bridging make it a capable fit for that work. Look elsewhere if your users and groups must come from more than one LDAP server.